Recently a potential, non-invasive alternative to bariatric surgery, a duodenal-jejunal bypass liner (EndoBarrierTM) has been introduced. It is an endoscopically implantable and removable device that prevents contact between partially digested nutrients and the proximal intestine. This device was shown to reduce body weight and to improve glycaemic control in subjects with diabetes. Small pilot studies suggested a change in incretin levels, similar to that observed after gastric surgery with an improvement of insulin sensitivity and glucose metabolism. To better understand and characterize the hormonal and/or metabolic effects after the implantation and removal of the EndoBarrierTM, this monocentric, prospective, trial is being performed.